Quasi,s Race bike Dyno chart

[Quasievil]

Nice gains at the top end. What I don't understand is why the graph is in MPH and not RPM.

The large increase in HP at low revs I consider to be in an area you would probably only notice on the road as most of the time your reving up near max power. Even launching off the line you'd be reving high and feathering the clutch.

Are you running an air filter? If so is it standard or aftermarket

i got another graph that shows the RPM as well.
standard air filter, very hard to adjust much here they run so tight in relation to the air intake etc, they tried a few things but nothing would work

[TwoSeven]

Can you post the RPM one as well it would be interesting.

I have a silly question tho. My understanding is the bike is a track bike. So I am wondering why effort was spend wasting valuable engine resource filling out the flatspot below 5k rpm. There is a potential 1000rpm wasted down there that could have been used better up at the top end.

I could understand if its a road bike where you'll be using low down rpm - but even then, I dont think I can ever remember riding an inline-4 down that low in the rev range. Its why I am interesting in the dyno char with rpm on it.

[cowpoos]

interesting too, that you had a slightly lower ambient pressure on the 2nd run, which (unless the machine is calibrated to take notice of it) will result in a slight lowering of performance - like an increase in altitude.

no.....more power.....cooler temp air....more dense air....more O2 in the engine....more power....

Altitude is a whole nother storie

[Quasievil]

Can you post the RPM one as well it would be interesting.

I have a silly question tho. My understanding is the bike is a track bike. So I am wondering why effort was spend wasting valuable engine resource filling out the flatspot below 5k rpm. There is a potential 1000rpm wasted down there that could have been used better up at the top end.

I could understand if its a road bike where you'll be using low down rpm - but even then, I dont think I can ever remember riding an inline-4 down that low in the rev range. Its why I am interesting in the dyno char with rpm on it.

The problem is that the bike has a close ratio gear box, typical of an SP model, and this means it is very very hard to get of the line, yes I have to feather the clutch to get the revs up but I still need low down torque to get away, this was the answer, now I have a smooth torque curve throughout the rev range and starts are alot better now as well.

Here is the other graph

[TwoSeven]

I know what your getting at - its the easy and cheap mod that fixes the problem - so all is good - xactly what I would do

I figure your peak torque is about 10.5k rpm (roughly) which is pretty much where i'd try to set the throttle on the start. Problem is likely to be a bit of front wheel lift.

To me a close ratio gearbox simply means there is more overlap on each gear - not to be confused with a linear gearbox which means there is almost no overlap. The close ratio simply means that it wont drop down so many rpm when changing gear (and wont rise so many rpm when I change down) - this means that each gear overlaps the ones either side more.

To get round the overlap problems I'd shortshift some gears (almost a certain if the bike was designed for the road). I figure there is no point staying in a lower gear in the middle of the power band when I could be in a higher gear lower in the power band (wider amount of drive).

Its not much to do with the way torque is delivered to the rear wheel, other than the actual ratio number itself (adding more power increased torque which is what the needle change did).

Looking at the first gear ratio on the stock bike - it does appear to be somewhat crap (ie. its worse than a cbr250). I'd try either starting in 2nd, or short-shifting into 2nd at about 50km/hr (this will probably prevent the wheelie as well). If it still wheelies - i'd try setting the throttle lower say at 9.5k and shifting as soon as you hit 50km/hr (this is a short shift). I'd probably want to go into 3rd at about 100k (another short shift - the joys of close ratio)

It does look like (from the interweb) the internal ratios were designed for 180km/hr tops - which is common for jap bikes.

I have a couple of more silly questions - did you find out what year cbr the camshaft was from and was it inlet/exhaust or both ?

The other one, is I take it you already have a 520 pitch chain fitted ?

[cowpoos]

fuckin hell......the way people throw around the words torque and horse power....peak power....torque curve does this and that.....

I bet not one of you know how either operate....what they mean and or do....or there relivance.....

[cowpoos]

infact i wonder if anyone on this site knows the way everyone use's the terminology with no idea

[Kickaha]

infact i wonder if anyone on this site knows the way everyone use's the terminology with no idea

Well we will just have to defer to your obviously superior knowledge on all things motorcycle related

forgive us Master we're not worthy

[Quasievil]

Well I dont have a fucken clue about most Bike tech stuff, but thats why I ask so much on KB, I always get answers and direction on everything I need, tis bloody great

[cowpoos]

Well we will just have to defer to your obviously superior knowledge on all things motorcycle related

forgive us Master we're not worthy

well explain it then.....I'll give you rep if you get it right....

or prove your a ignorant prick by saying nothing....

[TwoSeven]

infact i wonder if anyone on this site knows the way everyone use's the terminology with no idea

Lol. when you get some experience in life, you'll realise its often not what people say but why they say it thats important. It doesnt bother me if people (me included) use the wrong terminology, so long as the gist is understood.

[SPORK]

infact i wonder if anyone on this site knows the way everyone use's the terminology with no idea

I wonder if you know how to use apostraphes correctly?

Any "guesse's"?

Don't go off your nut at people because they're trying.

[Kickaha]

well explain it then.....I'll give you rep if you get it right....

or prove your a ignorant prick by saying nothing....

I resent that remark I can prove I'm an ignorant prick whether I say something or not

get over yourself

Lol. when you get some experience in life, you'll realise its often not what people say but why they say it thats important. It doesnt bother me if people (me included) use the wrong terminology, so long as the gist is understood.

Well fuck me, for once I agree with you

[cowpoos]

Lol. when you get some experience in life, you'll realise its often not what people say but why they say it thats important. It doesnt bother me if people (me included) use the wrong terminology, so long as the gist is understood.

I find if what people say is based on miss information or opinions that have no bearing on truth all your doing is misleading people...and there decisions on whats correst and incorrect....

I'm not acctually talking about terminology....I'm talking about the whole subject....people think torque does this or that and power this but not that...
It is such a simple subject that is so often talked about with very very little understanding....what most people know about it is acctuually nothing...because some where along the line some one made up a hold lot of crap to explain what they didn't know....

Okay.....rep for anyone that can explain....what torque/horsepower are and what the do....and there relation to engine performance

[cowpoos]

[QUOTE=Kickaha]I resent that remark I can prove I'm an ignorant prick whether I say something or not

get over yourself

QUOTE]

well explain you knowledge of this subject....or shut up....simple....

being a smart arse does make you sound ignorant...

and I'll take that all back if you explain....what are you scared of????